First-line anti-tuberculosis drug resistance patterns and trends at the national TB referral center in Iran—eight years of surveillance

Abstract

There has been an increasing trend in drug resistance in recent years, particularly in retreatment cases. Hence, revision of the national TB control program, reevaluation of the role of the World Health Organization category II (CAT II) regimen, as well as the conducting of a nationwide drug resistance survey, are recommended.

Challenges of Tuberculosis in Iran

“…16 times less than that among Afghans (22). Afghan patients include more than half of the multidrug-resistant tuberculosis cases in Iran, which reflects insufficient health services and surveillance infrastructure in their country (23). In a survey conducted by Farnia et al the rate of reactivation versus recent transmission was evaluated among Afghan and Iranian relapse cases and the impact of Afghan immigrants on the national tuberculosis control program of Iran due to intracommunity transmission between Afghan and Iranian tuberculosis cases was highlighted (24).…”

“…It has also been demonstrated that the patients infected with rifampicin resistant strains will encounter a higher failure rate with short-course 6-month chemotherapy (32). These patients require treatment for at least two years while the treatment is 70 times more costly accompanied by much higher mortality rate (about 40% -60%) (23). In different parts of the world, multiple types of mutations have been identified in rifampicin-resistant M. tuberculosis clinical isolates, most of which are 10 codon point mutations, while only a few isolates have insertion or deletion.…”

“…In the studies conducted in Iranian settings, drug resistance to streptomycin has been found to have the highest proportion among anti-tuberculosis drugs, followed by isoniazid with 23% resistance in new cases of tuberculosis (23,40,41). The high prevalence of streptomycin resistance isolates may be due to the previous usage of other aminoglycosidal drugs for the treatment of different infectious diseases, like brucellosis, which can result in crossresistance (23).…”

“…The high prevalence of streptomycin resistance isolates may be due to the previous usage of other aminoglycosidal drugs for the treatment of different infectious diseases, like brucellosis, which can result in crossresistance (23). This high rate of streptomycin resistance has very important implications for tuberculosis control strategies since it would make treatment regimens less effective (40).…”

“…These two infections have a synergistic effect on each other. HIV infection, particularly advanced HIV infection (AIDS), is more critical than any other risk factors for the disease progression of recent or remotely acquired tuberculosis infection, both of which are major public health concern in numerous parts of the globe (23). Similarly, HIV infection is one of the most important risk factors promoting progression of latent tuberculosis infection to active tuberculosis disease in people with M. tuberculosis infection (77).…”